Valve grinding machine



NOV. 19, 1940. [HALL ETAL 2,221,918

VALVE GRINDING MACHINE Filed Oct. 21, 1938 4 Sheets-Sheet 1 frnes/ A. H0// Ken/762% ff 50/20 Nov, 19, 1940. L ETAL 2,221,918

VALVE GRINDING MACHINE Filed Oct. 21, 1938 4 Sheets-Sheet 2 l I E; E.

v%/% A 0 52 J- 5/ NOV. 19, E A. HALL HAL I VALVE GRINDING MACHINE Filed Oct. 21, 1938 4 Sheets-Sheet 3 I [/7785/ 14. //0// K n/76177 A. ab/7 Nov. 19, 1940. E. A. HALL ErAL VALVE GRINDING MACHINE 4 Sheets-Sheet 4 Filed Oct. 21, 1938 l l I I I gin/0244M 157/7052 A. /%0// Aennef/z fi 506/? WWW Patented Nov. 19, 1940 UNITED .s'rATEs'- PA NT;YQFF

vanvncnmnnvc MACHINE Ernest A. Hall and Kenneth B. Bohn, Toledo, Ohio, minors to The HalfManufacturing Company, Toledo, Ohio, a corporation of Ohio Application October 21. 1938, Serial No. 236,238

6 Claims.

In the gauging and grinding of valve stems for a set of valves to make each valve stemof proper length and clearance, which usually differs from the several valves of a set, it has heretofore been the practice, so far as I am aware, to first gauge and grind one valve stem and then another and necessitating a separate setting of the grinding machine for each valve stem.

One of the objects of the present invention is the provision of certain improvements inthe grinding machines for such valve stems, whereby after the several valve stems of a set have been first gauged as to proper length and clearance and such information noted as to each valve, the grinding machine, by the use of a length determining gauge, may then be initially set to suit the noted reading for the first valve 25 to be ground and thereafter be quickly secondarily adJusted to suit the length requirement for each successive valve of the set without further use of the length gauge and without necessitating repeated trips between the engine block and the grinding machine and entirely separate adjustments for each valve, thus saving labor, time and expense in the operation.

A further object of the invention is the provision in a valve stem grinding machine of a 35 mounting means for the valve stems that is capable of movement to rotate about its axis during a grinding operation.

A further object of the invention is the provision of simple and eflicient means for rotating the valve stem during a grinding operation.

A further object is the provision in a machine of the class described of means for angularly adjusting the valve stem support relative to the grinding member to permit grinding a stem end 45 in right angular relation to the stem axis or at a predetermined inclination to such right angular position to produce a centered protuberance or crown on the stem end.

Further objects and advantages of the inven- 50 tion will be apparent from the following detailed description and from the accompanying drawings, in which- Figure 1 is a plan view of a valve grinding machine embodying the invention, with a valve 55 mounted therein and disposed in grinding relation to the grinding wheel to grind the stem end in right angular relation to its axis; Fig. 2 is a side elevation of the machine, with parts broken away to show the manner of mounting of a valve 60 and its stem therein and the feeding means therefor; Fig. 3 is an enlarged cross-section on the line 3-3 in Fig, 1; Fig. 4 is an enlarged fragmentary section on the line 4-4 in Fig. 1; Fig. 5 is an enlarged sectional detail of the valve stem mounting means with such means adjusted to place the axis of the valve stem slightly out of true right angular relation to the grinding wheel face to permit the grinding of a crown on the stem end; Fig. 6 is an enlarged detail of the grinding coaction of a stem end and grinding wheel; Fig. 7 is an enlarged section on the line,,

. 6-6 in Fig. 1; Fig. 8 is a fragmentary end View of the machine similar to Fig. 2, with a mechanical rotating means applied to the valve stem mounting; Fig. 9 is a fragmentary plan view of the machine shown in Fig. 8, with parts broken away, illustrating the application of the valve stem mount driving means; Figs. 10 and 11 are fragmentary sections on the lines iii-40 and illl, respectively, in Fig. 9; Fig. 12 is a side elevation of a valve length gauge adapted for use in connection with the machine and illustrating the gauging position in a cylinder block, and Fig. 13 is a somewhat diagrammatical illustration of the index portion of the length gauge to illustrate its action.

Referring to the drawings, i designates the main frame of a valve grinding machine embodying the invention on the top of which, at one end thereof and at its rear portion in the present instance, is mounted a motor 2 and in advance of this a bearing frame 3 having a grinding wheel carrying shaft 4 mounted therein lengthwise of the frame or substantially in parallel relation to the front and rear sides of the frame, The shaft 4 carries at its outermost end a pulley i by which it is connected through a belt 6 to a pulley ion the motor shaft and carries at its inner or opposite end a grinding wheel 8 which, in the present instance, is disposed near the central portion of the frame I.

A table i0 is mounted for forward and rearward sliding horizontal adjustment on the top of the frame I at the end-thereof opposed to that on which the motor 2 and grinding wheel are mounted, and carries a head H disposed at a side of the grinding wheel 8 and positioned with the axis of its chuck 12 (Fig. 9) disposed at an oblique angle, to the grinding wheel axis, as well understood in the art. The chuck i2 is carried within a sleeve l3 which is rotatably mounted in the head II and carries at its rear end a pulley i 4 that is connected by a belt 15 to a drive pulley I8. The pulley I6 is connected by a flexible shaft l'l which is connected to and driven by a pulley l8 connected by a belt l9 to a small pulley on the motor shaft. The chuck head II is mounted for axial adjusting movements on the table I 0. This adjustment, however, has nothing to do with the present invention and need not, therefore, be described. When a valve is having its seating surface ground, its stem is engaged within the chuck l2.

Adjustment is imparted to the table M by turning a hand wheel 2i attached to a screw shaft 22. This shaft is rotatably mounted in a flange 23 at the front end of the table in a manner to prevent axial movements of the screw shaft therein and has its rear end threaded through a bushing 24 fixedly mounted in the frame I. For the purpose of the present invention, a bracket plate 28 is mounted on the forward end of the table i0 transversely thereof and has one end projecting beyond the inner edge portion of the table and provided with a valve carrying head 29 in advance of the circumferential grinding face of the grinding wheel 9. The head 29, in the present instance, is mounted for forward and rearward adjustment on the plate 28, being secured in adjusted position by a clamping screw 30 (Fig. 2) extended through the plate 29 and threaded into said head.

A valve head carrying sleeve ii is rotatably mounted in the upper end of the head 29 with its axis substantially aligned with a radius of the grinding wheel 8 and its inner end spaced outwardly a distance from the periphery of such wheel, as best shown in Fig. 2. In the present instance, the outer end of the sleeve 31, is enlarged and shouldered against the head 29 and its inner end extends beyond such head and has a collar 32 threaded thereon and in yielding and thrust engagement with the adjacent end of the head through an interposed spring washer 32 which permits limited outward yielding movements of the sleeve relative to the head 29. The outer enlarged end of the sleeve 9| is provided with a conical countersink 93 extending to the bore of the sleeve and being complemental to and adapted to form a seat for a valve head a, the stem b of which is projected inwardly through the sleeve. The sleeve bore is of greater diameter than the valve stem so that the only point of contact of the valve with the sleeve is through the head of the valve seated in the conical sleeve end. The means illustrated for clamping avalve to the sleeve 3| includes, as best shown in Fig. 5, a gate member 34 extending across the outer enlarged end of the sleeve 3| hinged at one end thereof to the sleeve end and having its other end releasably held to the sleeve by a hand screw 35. A clamping screw 35' is threaded centrally through the member 34 and is adapted to coact at its inner end with the valve head a to hold it to its seat. The screw 35 has its outer end bent in crank form to facilitate a turning thereof and also of the sleeve 3| and engaged valve when the valve is clamped therein.

The free end portion of the valve stem b projects beyond the inner end of the sleeve 3| and is supported in axially aligned relation to the sleeve by a member 36. This member, in the present instance, is in the nature of a disc (see Fig. 3), having a plurality of stem seating re-,

cesses 31 in spaced relation around its periphery and adapted to be moved into valve stem supporting position by a turning of the disc. Valve stems vary in diameter, but customarily are V4, or of an inch in diameter, and the disc 36 is, therefore, preferably provided with five circular valve stem receiving recesses, having different diameters suited to such dimensions. This enables any valve having a stem of one of the prescribed sizes to be firmly seated in a disc recess which has been positioned in valve stem supporting relation. The disc 29 is rotatably mounted on a stub shaft 39 projecting from a bracket 99 rising from the inner portion of the plate 29. The disc is-held in any adjusted position by engagement of a retractable detent' pin 40 with a registering opening ll in the disc. The pin 40 is mounted in the bracket 39. When a valve stem is held seated in a recess of the support 29, it is held therein by a lever 42 which is fulcrumed to the bearing bracket 39 at 43 and has one arm engaging over the top of the valve stem, and its other arm serving as a handle. The coiled contractile spring 44 engages the lever and normally retains it in holding engagement with the valve stem.

It is apparent from the foregoing that when a valve and its stem are properly mounted in the sleeve 3| and on the support 39, the valve is firmly held to its seat in the sleeve 3| coaxially therewith by the clamping screw 35 and when so clamped is permitted to have limited outward axial movements with the sleeve due to the interposing of the spring spacing member 92* between the sleeve collar 92 and the head 29. when the valve has been thus positioned in the holding means, its stem may be disposed in true radial relation to the grinding wheel or in slightly angled position relative thereto, depending on whether or not it is desired to grind the stem end in flat or crowned form. A stem when mounted in the holding means may be moved into or out of engagement with the grinding surface of the grinding wheel by a turning of the hand wheel 2| which effects an adjustment of the table l0, and should the pressure of the stem end against the grinding wheel during such an adjustment be too heavy, the spring 92 will yield to permit an outward movement of the stem and its mounting means relative to the grinding wheel. when the valve stem end is to be ground to form a right angular bearing face, the valve stem is positioned with its axis in true radial relation to the grinding wheel, so that the wheel periphery has substantially a line contact with the stem end entirely across the latter axially of the wheel, and when the stem is thus engaged with the wheel a uniform grinding of its end is effected by a turning of the stem about its axis relative to the wheel. This turning may be effected manually by grasping and turning the outer end of the sleeve 9i.

To permit an angular adjustment of the valve stem relative to the grinding wheel and in a plane substantially parallel to the grinding wheel axis, so as to place the end surface of the stem at an acute angle to the circumferential face of the grinding wheel and thus efiect what may be termed a crown grinding of the stem end, the bracket plate 28 is mounted for limited horizontal rocking movement on the table it. To accomplish this, the plate 28 has a pivot pin 50 projecting into a transversely disposed surface groove II in the table I0 and theplate is provided in outwardly spaced relation to such pin with a revoluble eccentric stud 52, which, in the present instance, is engageable in an extended end portion of the groove 5|. The stud 52 is provided at the end of the stub shaft 53 which is mounted in a vertical opening in said plate, being held therein, and also being locked in adjusted position, by a screw 54 engaging a circumferential recess in the shaft. The plate 29 is clamped in adjusted position to the table II by thumb screws 55, the stem portions of which extend through enlarged openings 58 in the plate and thread into the table. The openings 38 are of a size suitable to permit anydesired lateral adjustment of the plate 28 when the clamping screws are loosened. A swinging adjustment of the plate 28 about its pivot 50 effects an angular shifting of the stem axis of a valve carried by the plate relative to a radial line of the grinding wheel, so that the circumferential grinding face of the wheel, presuming it to be parallel to the wheel axis, will stand at a slight angle to a diametrical end plane of the stem, thus causing the stem end to be ground in substantially conical or crown form when the valve is rotated about its axis for such purpose. The portion of the valve stem end which is engaged by the grinding wheel during the grinding action is preferably less than the length of a radial line of such end, so that the ground end of the stem when finished will be of substantially truncated form, as illustrated by Fig. 6.

The purpose and importance of effecting a crown end grinding of a valve stem forms no part of the present invention and need not, therefore, be described. This feature is covered by a copending application.

A power drive forthe valve carrying sleeve 3| is illustrated in Figs. 8 and 9 and may be substituted for the hand drive accomplished through grasping the outer end of the sleeve 3| and turning it in the head 29. The collar 32 on the inner end of the sleeve 3| is replaced by a spiral gear 82 that may be threaded on the sleeve and which is engaged by a drive pinion 63, the shaft 84 of which is journaled in a bearing plate 65 secured to the top of the bearing head 29. The axis of the shaft 88 is parallel to the axis of the chuck l2 and carries a pulley 68 which is connected by a belt 81 to a pulley 88 fixedly mounted on the end of a stem 89 adapted to be engaged within the chuck l2. It is thus apparent that the drive for the valve holding sleeve 3| is connected to the chuck l2 and through it with the. drive means therefor.

It is apparent that when a valve is properly mounted in the holding means of the plate 28 and the valve is rotated, either manually or mechanically, the valve stem b turns with the sleeve 3|, which constitutes the driving element therefor, and on the support 36, and that the lever 42 merely acts to hold the valve stem to its seat on said support and not to prevent it from turnmg.

To facilitate the successive grinding of all of the valves of a set for which the proper length measurements have been obtained, as hereinafter described, and to obviate the initial adjustment of the machine for each valve, thus simplifying and minimizing the grinding expense for a valve set, the screw adjusting means 2|, 22, for the table I0 is provided with a secondary adjusting feature, the purpose of which will later be more fully described. This secondary adjusting feature comprises, in the present instance, a slip ring 18 mounted for frictional turning movements on the feed wheel 2|, and is provided on its periphery with graduations corresponding to those on the dial of a length measuring gauge, as hereinafter described, which graduations are such as to register the feeding movements of the wheel 2| in thousandths of an inch. These graduations register with a fixed point on an adjacent portion of the table I8, as indicated at H in Fig. 1.

In practice, it is customary to provide a clearance of approximately .013 of an inch between the end of the valve stem and the associated tappet rod when the valvehead is properly seated and the tappet rod is fully retracted. To determine the length of a valve stem for any particular valve seat, a length gauge G, such for in- 5 stance as shown in Fig. 12, is employed. While any auge suitable for the purpose may be used, the gauge illustrated comprises a head 88 carrying a gauge index unit 8| with its revoluble index finger 82 connected through suitable intermediate gearing with a rack bar 83. The upward movement of the rack baris resisted by a spring 84, as shown in Fig. 13. The head 80 is provided at its lower end with a stop shoulder 85 having a surface complemental to and adapted to bear against the associated valve seat of a cylinder block in the manner of a valve. A gauge rod 88 is reciprocably mounted in an opening provided centrally through the lower neck portion of the head and bears at its upper end against the lower end of the rack bar 83. The rod 88 is slightly greater in length than the distance between the rack bar 83, when normally extended, and the asssociated tappet 81 when the shoulder 85 is on the valve seat, so that by forcing the shoulder down onto said seat, with the rod 88 seated on the tappet, the rack bar 83 will be caused to move upward and effect a consequent movement of the index finger about the dial face, as shown in Fig. 12, where the indicated reading is 12," meaning .012 of an inch, the graduations being in thousandths. The valve for the gauged seat is then marked 12, or a suitable notation to that effect made in a manner to be identified with the particular valve.

In practice, it is preferable to gauge the cylinder block to determine the length requirements for all of the valves used and making a notation with respect to each valve for its respective gauge reading, and also marking each valve in a manner to identify it with the particular valve seat, before any of the valves are ground.

In the use of the machine in connection with the grinding of valve stems to proper length, the gauge G is first placed in a valve seat opening to measure the distance between the valve seat and tappet and to indicate on its dial a fraction of such distance in thousandths of an inch. The reading on the gauge shown in Fig. 12 is 12. This reading is marked on the valve for the valve opening measured, or is otherwise suitably noted in identifying relation to the valve, and the measuring of the remaining valve openngs of the cylinder block and the noting of the gauge readings for the respective valves and openings is then effected in the same manner, preferably before starting the grinding of the valve. The valves are then taken to the grinding machine and the initial setting of the machine for ail of the valves of the set is determined by the gauge reading noted with respect to the first valve to be ground. To effect the proper initial adjustment, the gauge is applied to the machine by inserting the gauge rod 88 through the valve holding sleeve 3| until the gauge shoulder 85 seats against the conical seating surface 33 of the sleeve in the same manner that a valve head a seats thereagainst. The feed wheel 2| is then turned to move the table l8 and parts carried thereby rearward until the end of the gauge rod 86 engages the periphery of the grinding wheel 8. When such engagement takes place, the feeding movement is continued until the gauge rod 88 has been moved outward, during a continued seating of the shoulder 85 against 75 the sleeve, a suflicient distance to actuate the gauge of the measuring instrument to indicate a reading of .012 of an inch. The slip gauge ring 10 is then turned on the feed wheel 2|, relative 5 thereto, to place the ring graduation which indicates .012, in register with the assoc ated stationary index mark on the machine. This constitutes the initial setting of the machine for the entire set of valves. The gauge is now removed and the valve, identified by the "12 notation, is properly mounted in the sleeve 3| and on the support 36, as best indicated in Fig. 2, with its head in stop engagement withthe sleeve face 33, and the outer end of the stem is then ground l5 to the extent permitted by the gauge setting of the machine. If the desired clearance is .013 meaning thirteen thousandths of an inch, the feed wheel, together with the gauge ring Hi frictionally engaged therewith, is turned during the grinding until the graduation mark 25 (12 plus 13) on the gauge ring has been turned into register with the stationary index po nt ll, thus further reducing the length of the valve stem the extent of thedesired clearance. If the marking for the next valve to be ground is say 15, the feed wheel 21 is turned to place the gauge mark on the gauge ring into register with the stationary mark 71, and, as the grinding of the valve continues, the feed wheel is slowly turned to add the desired .013 clearance, which in this case would be determined when the feed wheel had been turned .to place the "28 graduation mark in register with the index point. It is apparent that the grinding of a number of valves '35 may be accomplished by only one use of the gauge G in connection with the grinding machine to obtain an initial setting thereof, after which the machine may be adjusted in accordance with the readings noted in connection with d fierent 40 valves without again placing the gauge in the machine, and that considerable time and labor required in the grinding of valve stems to the desired length for the engine in which they are to be used is saved.

45 During a stem end grinding operation, the valve may be rotated about its stem axis by a manual turning of the carrying sleeve 31 or mehanically by connecting such sleeve with a power source, as shown in Figs, 8 and 9. Also, that the mounting means for the valve may be adjusted to dispose the valve stem axis in true radial relation to the grinding wheel to efiect a flat grinding of the stem end or that it may be adjusted so as to effect a grinding of its stem end in a 55 plane which is out of parallel with the grinding face of the wheel, whereby to cause a crowned grinding of the stem end when the stem is rotated during the grinding action. It is also apparent that the spring washer member 32 acts to normally retain the valve holding sleeve 3| at the limit of its inward movement and is adapted to permit limited outward yielding movements ofthe sleeve and valve in the event a valve stem, during an adjusting movement, is brought against the grinding wheel with too great a pressure.

We wish it understood that our invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications and changes without departing from'the spirit of the claims.

Having thus described our invention, what we claim as new, and desire to secure by United States Letters Patent is:

1. In a 'valve grinding machine, means for hold- 7 ing a valve during an end grinding of its stem,

said means comprising a mount, a sleeve rotatably carried by the mount and forming a seat at one end for the valve head and adapted to have the valve stem project axially therethrough, and a support for the end of the valve opposed to its head to hold the stem in coaxial relation to the sleeve, said support having a plurality of seats therein for valve stems of diflerent diameters and adjustable to place any seat in stem supporting position.

2. In a valve grinding. machine, means for holding a valve during an end grinding of its stem comprising a reciprocable movable table, a bracket plate carried by said table for pivotal adjustment relative thereto, a sleeve rotatably carried by said plate for rotation about its axis and having a valve head seat, means for yieldingly holding a valve and said sleeve with the valve stem projecting through and beyond the sleeve, and a valve stem support carried by said plate and cooperating with said sleeve to hold a valve stem in coaxial relation to the sleeve and permitting turning of the valve with the sleeve.

3. In a valve grinding machine, means for holding a valve during an end grinding of. its

stem, said means including a member against in stem supporting position, and means for re-- leasable engaging the valve stem to hold it to its seat in said support.

4. In a valvegrinding machine, means for holding a valve during an end grinding of its stem,

. one end of its said axial movement, and meanscooperating with the sleeve to hold a valve to its seat therein with its stem projecting therethrough and beyond its opposite ,end. I

5. In a valve grinding machine, means for holding a valve during an end grinding of said stem, said means including a member against which a valve head may seat, means for holding a valve to its seat in said member, a separate cooperating support for the valve stem having a plurality of seats for receiving stems of difierent diameters and being adjustable to-place any seat in stem supporting position.

6. In a valve grinding machine, means for holding avalve'during an end grinding of its stem, said means including an adjustable mount, a sleeve carried by the mount for rotation about its longitudinal axis during a grinding operation and having shouldered coaction with the mount to limit any axial movement of the sleeve relative thereto during rotation and a grinding operation, said sleeve having a valve head set at one end, means cooperating with the sleeve to hold a valve to its seat therein with its stem projecting longitudinally therethrough and beyond its opposite end and for rotation with a sleeve, and a support separate from the sleeve and not rotatable therewith for holding the valve stem in coaxial relation to the sleeve and permitting turning of the valve with the sleeve.

ERNEST A. HALL. KENNETH R. BOHN. 

